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排序方式: 共有101条查询结果,搜索用时 15 毫秒
71.
72.
In this paper, we establish several inequalities for some differantiable mappings that are connected with the Riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementar... 相似文献
73.
Tamer Dogan Hasan Cetin Zehra Yegingil Mustafa Topaksu Mehmet Yüksel Fırat Duygun 《辐射效应与固体损伤》2013,168(7-8):630-644
In this study, the optically stimulated luminescence dating technique was used to determine the time of deposition of alluvial sediment samples from the Türko?lu-Antakya segment of the East Anatolian Fault System (EAFS) in Turkey. The double-single aliquot regenerative dose protocol on fine grain samples was used to estimate equivalent doses (De). Annual dose rate was computed using elemental concentration of uranium (U) and thorium (Th) determined by using thick-source alpha counting and potassium (K) concentrations using X-ray fluorescence and/or atomic absorption spectroscopy. The environmental dose was measured in situ using α-Al2O3:C chips inside plastic tubes for a year. The two different bulk sediment samples collected from the Islahiye trench yielded ages of 4.54?±?0.28 and 2.91?±?0.23?ka. We also obtained a 2.60?±?0.18?ka age for the alluvial deposit in the K?ranyurdu trench and 2.31?±?0.14?ka age for an excavation area called Malzeme Oca??. These ages were consistent with the corresponding calibrated Carbon-14 (14C) ages of the region. The differences between the determined ages were insufficient to clearly distinguish the disturbance event from the effects of bioturbation, biological mixing, or other sources of De variation in the region. They provide a record of alluvial aggradation in the region and may determine undocumented historical earthquake events. 相似文献
74.
Probe vehicles are increasingly receiving more attention as an alternative means of collecting real-time traffic data needed for system optimization. This paper focuses on real-time estimation of queue lengths from the location information of probe vehicles in a queue at an isolated and undersaturated intersection. The paper also addresses the evaluation of the accuracy of such estimates as a function of the market penetration of probe vehicles. An analytical formulation based on conditional probability distributions is developed for estimating the expected queue length and its variance. It is found that, for the given settings, only the location information of the last probe vehicle in the queue is sufficient for the estimation. Exact expressions for the conditional mean and variance of queue length are derived. Various numerical results are documented to show how estimation errors behave by the volume to capacity ratio and by market penetration. 相似文献
75.
SnO2 is a prototype "transparent conductor," exhibiting the contradictory properties of high metallic conductivity due to massive structural nonstoichiometry with nearly complete, insulator-like transparency in the visible range. We found, via first-principles calculations, that the tin interstitial and oxygen vacancy have surprisingly low formation energies and strong mutual attraction, explaining the natural nonstoichiometry of this system. The stability of these intrinsic defects is traced back to the multivalence of tin. These defects donate electrons to the conduction band without increasing optical interband absorption, explaining coexistence of conductivity with transparency. 相似文献
76.
Cetin Bayrak Halil Senol Sedef Sirtbasi Ertan Sahin Abdullah Menzek 《Tetrahedron》2018,74(40):5839-5849
Reactions of benzyne with ester derivatives of spiro[2.4]hepta-4,6-dien-1-ylmethanol were performed. By rearrangement reaction of cyclopropyl methanol units of ((1s*,1′R*,2R*,4′S*)-1′,4′-dihydrospiro[cyclopropane-1,9'-[1,4]methanonaphthalen]-2-yl) methyl 3,5-dinitrobenzoate (13) and its isomer (14), corresponding allyl chlorides were obtained. Two rearrangement products were obtained from bromination of compound 13 with an equivalent amount of Br2. A naphthalene derivative including allyl and CHO moiety was formed for reactions from compounds with epoxide of 13 and 14 with NaN3 by sequential rearrangements. Formations of products are discussed. 相似文献
77.
In this study, (1R,2R)-1,2-bis-(5-amino-1,3,4-thiadiazol-2-yl)ethane-1,2-diol (2), was synthesized by using (2R,3R)-(+)-Tartaric acid (1) as starting compound. Then the diazo component 3 was obtained from 2 and 1-naphthol. In addition, the structures of the synthesized compounds 2 and 3 were confirmed by elemental analyses, IR, 1H-NMR, and 13C-NMR spectra.
__________
Published in Kimiya Prirodnikh Soedinenii, No. 5, pp. 465–466, September–October, 2005. 相似文献
78.
Herrick RS Ziegler CJ Jameson DL Aquina C Cetin A Franklin BR Condon LR Barone N Lopez J 《Dalton transactions (Cambridge, England : 2003)》2008,(27):3605-3609
The reaction of Re(CO)(5)Br with tris(2-pyridyl)methanol (tpmOH) leads to unexpectedly complex chemistry with three new compounds forming instead of a single product. In compound 1, the tpmOH ligand binds to the metal in the N,N',N'-mode; 2 has tpmO(-) bound in the N,N',O-mode; while 3 is a dimer with the tpmO(-) ligand utilizing each of the four donor atoms to bridge the two metal centers. The analogous methyl ether ligands, tris(2-pyridyl)methoxymethane (tpmOMe) or tris[2-(l-methylimidazolyl)]methoxymethane (timmOMe), each yielded a single product, 4 and 5, respectively, bound in the N,N',N'-mode, and are new leads for potential radiotherapeutic agents. All compounds have been structurally characterized. 相似文献
79.
Effect of Joule heating on electrokinetic transport 总被引:1,自引:0,他引:1
The Joule heating (JH) is a ubiquitous phenomenon in electrokinetic flow due to the presence of electrical potential gradient and electrical current. JH may become pronounced for applications with high electrical potential gradients or with high ionic concentration buffer solutions. In this review, an in-depth look at the effect of JH on electrokinetic processes is provided. Theoretical modeling of EOF and electrophoresis (EP) with the presence of JH is presented and the important findings from the previous studies are examined. A numerical study of a fused-silica capillary PCR reactor powered by JH is also presented to extend the discussion of favorable usage of JH. 相似文献
80.
S Chanda Sarmishtha Bhattacharyya Tumpa Bhattacharjee SS Ghugre Swapan Kumar Basu S Muralithar RP Singh B Mukherjee RK Bhowmik SN Ray 《Pramana》2001,57(1):175-179
The high spin states in N=80 139Pr have been investigated by in-beam γ-spectroscopic techniques following the reaction 130Te (14N, 5n) reaction at E=75 MeV, using a gamma detector array, consisting of seven 23% compton-suppressed high purity germanium detectors and a multiplicity
ball of fourteen bismuth germanate elements. Based on γ-γ coincidence data, the level scheme of 139Pr has been considerably extended up to 7.2 MeV excitation. Tentative spin-parity assignments are done for the newly proposed
levels on the basis of the DCO ratios corresponding to strong gates and the available information from the earlier light ion
experiments. 相似文献